Note the naming of the pods and replica set, derived from the deployment name.

At this point in time the sise containers running in the pods are configured
to return the version 0.9. Let’s verify that from within the cluster (using kubectl describe
first to get the IP of one of the pods):

If there are problems in the deployment Kubernetes will automatically roll back to
the previous version, however you can also explicitly roll back to a specific revision,
as in our case to revision 1 (the original pod version):